On using reduced networks for distributed DC power flow

The last decades have seen a big change in the European system of electric transmission grids. Liberalization, the influx of Information and Communications Technology and a strong growth in cross-border trading have changed the realities which grid operators face. Due to the rise in interaction between Transmission System Operator areas, primarily in terms of increased energy trading, there is an increased dependency on the state of the neighboring systems. In order to have a good estimate of the situation in the own area, the Transmission System Operator needs to have an idea what is happening in the other areas. This can be achieved either with full data sharing, or with decentralized calculation methods. There may be situations where complete data sharing is not applicable as Transmission System Operators are not willing, or able, to share the data. This paper presents a reduced decentralized calculation method which improves on previously proposed methods by speeding up calculation time. An iterative procedure is used to find the solution which all participants find suitable, under consideration of their own objectives. The new method is compared to the centralized, full-data, solution and a distributed method where the full system model is used.